1,721,094 research outputs found
Prediction of Air Permeability Using a Finite Element Method
No full textAir permeability is one of the most important parameters in the study of thermo-physiological comfort of fabrics. The main goal of this work is to develop a virtual process that allows the prediction of air permeability of any fabric without realizing a sample. The Free and Porous Media Flow physics interface was used in COMSOL Multiphysics® software; this allows to use Navier-Stokes equation in the air free volume through yarns and the Brinkman equation inside yarns. This work confirms that air permeability can be predicted with good accuracy, from the basic design parameters of any fabric
The phase partition of disperse dyes in the dyeing of polyethylene terephthalate with a supercritical CO2/methanol mixture
No full textThe aim of the work was to investigate the effect of methanol addition on the dyeing of a commercial polyethylene terephthalate (PET) yarn with supercritical carbon dioxide. The solubility in the supercritical bath and the equilibrium uptake in the yarn have been measured for two azo dyes at different working conditions (353.2-393.2 K, 16-24MPa). The partition coefficients between the phases were evaluated and compared with the data obtained without any modifier. It was found that the presence of methanol increases the dye concentration in the yarn and the dye solubility in the supercritical phase, and allows good dyeing results to be obtained at less severe working conditions. Both the dye solubilities and the equilibrium partition coefficients between the phases were satisfactorily correlated with some density-based equations available in literatur
Proceedings of World Textile Conference AUTEX2008 Biella June 24-26, 2008 Book of Abstracts and Full Paper CD-ROM
No full textA comparison of analytical methods for the quantificationof a reactive b-cyclodextrin fixed onto cotton yarns
No full textCotton yarns bobbins were treated in a water bath with different concentrations of a reactive b-cyclodextrin derivative. To quantify the amount of cyclodextrin fixed on the fiber different analytical methods were tested but none of them was reliable enough in the concentration range under investigation. Therefore, a new analytical method, fast and effective, was developed. From the measurement of cyclodextrin bath exhaustion, the amount of cyclodextrin chemically fixed and that physically adsorbed on the textile substrate was estimated. Two washing cycles were carried out to investigate the cyclodextrin washing fastnes
Supercritical dyeing of textiles - from the laboratory apparatus to the pilot plant
No full textSupercritical dyeing can be an interesting alternative to traditional dyeing due to the unquestionable advantage of the use of a clean solvent that can be easily recovered and separated from the excess dye at the end of the process. The experience achieved by our research group during a research project supported by the Italian government is reported in this work. The aim of the project was to set up a pilot plant where supercritical dyeing could be performed with yarn bobbins. In particular, this work shows the results obtained for polyester textiles. In the first part of the project, laboratory scale experiments were performed to determine the equilibrium partition of each dye between the two phases. In the second part, the pilot plant was set up. The dyeing results were successful: good reproducibility, together with a good dye uniformity and fastness (comparable with that of the traditional process) were obtained. The maximum productivity of the pilot plant is about 5 kg/h and the total duration of the dyeing process (approximately 1.5 h) is much shorter than that of the tradional method (3—4 h
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